Boar

Boars were a species of omnivorous mammals that are the ancestors of domesticated pigs. The word 'boar' usually, but not invariably referred to the male of the species.

Boars had gone extinct in England, but were later reintroduced in 1987. This occurred during a massive storm in Kent, when a farm that raised boars was damaged and the boars were allowed to escape. Some of these boars came to the house of the Doctor, and eventually evolved into the intelligent Boar race. (EDA: Mad Dogs and Englishmen)